Scandcleft randomized trials of primary surgery for unilateral cleft lip and palate : comparison of dental arch relationships and dental indices at 5, 8, and 10 years

Background and trial design The Scandcleft intercentre study evaluates the outcomes of four surgical protocols (common method Arm A, and methods B, C, and D) for treatment of children with unilateral cleft lip and palate (UCLP) in a set of three randomized trials of primary surgery (Trials 1, 2, and 3). Objectives To evaluate and compare dental arch relationships of 5-, 8-, and 10-year-old children with UCLP after four different protocols of primary surgery and to compare three dental indices. The results are secondary outcomes of the overall trial. Methods Study models taken at the ages of 5 (n = 418), 8 (n = 411), and 10 years (n = 410) were analysed by a blinded panel of orthodontists using the Eurocran index, the 5-year-olds' (5YO) index, and the GOSLON Yardstick. Student's t-test, Pearson's correlation, chi-square test, and kappa statistics were used in statistical analyses. Results The reliability of the dental indices varied between moderate and very good, and those of the Eurocran palatal index varied between fair and very good. Significant correlations existed between the dental indices at all ages. No differences were found in the mean 5-, 8-, and 10-year index scores or their distributions within surgical trials. Comparisons between trials detected significantly better mean index scores in Trial 2 Arm C (at all ages) and in Trial 1 Arm B (at 5 and 10 years of age) than in Trial 3 Arm D. The mean Eurocran dental index scores of the total material at 5, 8, and 10 years of age were 2.50, 2.60, and 2.26, and those of the 5YO index and GOSLON Yardstick were 2.77, 2.90, and 2.54, respectively. At age 10 years, 75.8% of the patients had had orthodontic treatment. Conclusions The results of these three trials do not provide evidence that one surgical method is superior to the others. The reliabilities of the dental indices were acceptable, and significant correlations existed between the indices at all ages. The reliability of the Eurocran palatal index was questionable.Peer reviewe

Validation of reference genes for quantitative RT-qPCR studies of gene expression in Atlantic cod (Gadus morhua l.) during temperature stress

<p>Abstract</p> <p>Background</p> <p>One important physiological response to environmental stress in animals is change in gene expression. To obtain reliable data from gene expression studies using RT-qPCR it is important to evaluate a set of possible reference genes as normalizers for expression. The expression of these candidate genes should be analyzed in the relevant tissues during normal and stressed situations. To find suitable reference genes it was crucial that the genes were stably expressed also during a situation of physiological stress. For poikilotermic animals like cod, changes in temperature are normal, but if the changes are faster than physiological compensation, the animals respond with typical stress responses. It has previously been shown that Atlantic cod show stress responses when elevation of water temperature is faster than 1 degree/day, for this reason we chose hyperthermia as stress agent for this experiment.</p> <p>Findings</p> <p>We here describe the expression of eight candidate reference genes from Atlantic cod (<it>Gadus morhua l</it>.) and their stability during thermal stress (temperature elevation of one degree C/day for 5 days). The genes investigated were: Eukaryotic elongation factor 1 alpha, <it>ef1a</it>; 18s ribosomal RNA; <it>18s</it>, Ubiquitin conjugate protein; <it>ubiq</it>, cytoskeletal beta-actin; <it>actb</it>, major histcompatibility complex I; MHC-I light chain, beta-2 -microglobulin; <it>b2m</it>, cytoskeletal alpha-tubulin; <it>tba1c</it>, acidic ribosomal phosphoprotein; <it>rplp1</it>, glucose-6-phosphate dehydrogenase; <it>g6pd</it>. Their expression were analyzed in 6 tissues (liver, head kidney, intestine, spleen, heart and gills) from cods exposed to elevated temperature and compared to a control group. Although there were variations between tissues with respect to reference gene stability, four transcripts were more consistent than the others: <it>ubiq</it>, <it>ef1a</it>, <it>18s </it>and <it>rplp1</it>. We therefore used these to analyze the expression of stress related genes (heat shock proteins) induced during hyperthermia. We found that both transcripts were significantly upregulated in several tissues in fish exposed to increased temperature.</p> <p>Conclusion</p> <p>This is the first study comparing reference genes for RT-qPCR analyses of expression during hyperthermia in Atlantic cod. <it>ef1a, 18s, rplp1 </it>and <it>ubiq </it>transcripts were found to be well suited as reference genes during these experimental conditions.</p

Enrichment of Artemia nauplii in vitamin A, vitamin C and methionine using liposomes

Several types of liposomes were used to enrich Artemia nauplii in vitamin A, vitamin C and free methionine. In a first experiment, unilamellar liposomes formulated with krill phospholipid extract and retinyl palmitate demonstrated their capability to enhance the retinol content of Artemia nauplii. Furthermore, the increase in retinol was related to the amount of retinyl palmitate included in the liposomes as vitamin A source. These findings yield the possibility of using such vesicles to bioencapsulate simultaneously both vitamin A and essential fatty acids present in the krill phospholipid extract. A second enrichment was carried out with unilamellar liposomes composed of soybean phosphatidylcholine and loaded with sodium ascorbate as vitamin C source. Our results did not show that vitamin C content in the nauplii could be increased using unilamellar liposomes. This was most likely due to the degradation of the vitamin C during enrichment as well as the ascorbate leakage. Finally, a third experiment assessed enrichment in free methionine using liposomes of different lamellarity (unilamellar or multilamellar) and composed of either soybean phosphatidylcholine or dipalmitoyl phosphatidylcholine, both combined with cholesterol as a membrane stabilizer. Results indicated that multilamellar liposomes represent a useful tool to deliver methionine to Artemia nauplii. Enhanced protection given by their multiple bilayers in comparison to unilamellar liposomes could account for the higher ability displayed by multilamellar vesicles for free methionine bioencapsulation

Atlantic cod (Gadus morhua) hemoglobin genes: multiplicity and polymorphism

Background: Hemoglobin (Hb) polymorphism, assessed by protein gel electrophoresis, has been used almost exclusively to characterize the genetic structure of Atlantic cod (Gadus morhua) populations and to establish correlations with phenotypic traits such as Hb oxygen binding capacity, temperature tolerance and growth characteristics. The genetic system used to explain the results of gel electrophoresis entails the presence of one polymorphic locus with two major alleles (HbI-1; HbI-2). However, vertebrates have more than one gene encoding Hbs and recent studies have reported that more than one Hb gene is present in Atlantic cod. These observations prompted us to re-evaluate the number of Hb genes expressed in Atlantic cod, and to perform an in depth search for polymorphisms that might produce relevant phenotypes for breeding programs. Results: Analysis of Expressed Sequence Tags (ESTs) led to the identification of nine distinct Hb transcripts; four corresponding to the α Hb gene family and five to the β Hb gene family. To gain insights about the Hb genes encoding these transcripts, genomic sequence data was generated from heterozygous (HbI-1/2) parents and fifteen progeny; five of each HbI type, i.e., HbI-1/1, HbI-1/2 and HbI-2/2. β Hb genes displayed more polymorphism than α Hb genes. Two major allele types (β1A and β1B) that differ by two linked non-synonymous substitutions (Met55Val and Lys62Ala) were found in the β1 Hb gene, and the distribution of these β1A and β1B alleles among individuals was congruent with that of the HbI-1 and HbI-2 alleles determined by protein gel electrophoresis. RT-PCR and Q-PCR analysis of the nine Hb genes indicates that all genes are expressed in adult fish, but their level of expression varies greatly; higher expression of almost all Hb genes was found in individuals displaying the HbI-2/2 electrophoretic type. Conclusion: This study indicates that more Hb genes are present and expressed in adult Atlantic cod than previously documented. Our finding that nine Hb genes are expressed simultaneously in adult fish suggests that Atlantic cod, similarly to fish such as rainbow trout, carp, and goldfish, might be able to respond to environmental challenges such as chronic hypoxia or long-term changes in temperature by altering the level of expression of these genes. In this context, the role of the non-conservative substitution Lys62Ala found in the β1 Hb gene, which appears to explain the occurrence of the HbI-1 and HbI-2 alleles described by gel electrophoresis, and which was found to be present in other fish such as eel, emerald rockcod, rainbow trout and moray, requires further investigation

Thyroid and pituitary gland development from hatching through metamorphosis of a teleost flatfish, the Atlantic halibut

Fish larval development, not least the spectacular process of flatfish metamorphosis, appears to be under complex endocrine control, many aspects of which are still not fully elucidated. In order to obtain data on the functional development of two major endocrine glands, the pituitary and the thyroid, during flatfish metamorphosis, histology, immunohistochemistry and in situ hybridization techniques were applied on larvae of the Atlantic halibut (Hippoglossus hippoglossus), a large, marine flatfish species, from hatching through metamorphosis. The material was obtained from a commercial hatchery. Larval age is defined as day-degrees (D =accumulated daily temperature from hatching). Sporadic thyroid follicles are first detected in larvae at 142 D (27 days post-hatch), prior to the completion of yolk sack absorption. Both the number and activity of the follicles increase markedly after yolk sack absorption and continue to do so during subsequent development. The larval triiodothyronine (T3) and thyroxine (T4) content increases, subsequent to yolk absorption, and coincides with the proliferation of thyroid follicles. A second increase of both T3 and T4 occurs around the start of metamorphosis and the T3 content further increases at the metamorphic climax. Overall, the T3 content is lower than T4. The pituitary gland can first be distinguished as a separate organ at the yolk sack stage. During subsequent development, the gland becomes more elongated and differentiates into neurohypophysis (NH), pars distalis (PD) and pars intermedia (PI). The first sporadic endocrine pituitary cells are observed at the yolk sack stage, somatotrophs (growth hormone producing cells) and somatolactotrophs (somatolactin producing cells) are first observed at 121 D (23 days post-hatch), and lactotrophs (prolactin producing cells) at 134 D (25 days post-hatch). Scarce thyrotrophs are evident after detection of the first thyroid follicles (142 D ), but coincident with a phase in which follicle number and activity increase (260 D ). The somatotrophs are clustered in the medium ventral region of the PD, lactotrophs in the anterior part of the PD and somatolactotrophs are scattered in the mid and posterior region of the pituitary. At around 600 D , coinciding with the start of metamorphosis, somatolactotrophs are restricted to the interdigitating tissue of the NH. During larval development, the pituitary endocrine cells become more numerous. The present data on thyroid development support the notion that thyroid hormones may play a significant role in Atlantic halibut metamorphosis. The time of appearance and the subsequent proliferation of pituitary somatotrophs, lactotrophs, somatolactotrophs and thyrotrophs indicate at which stages of larval development and metamorphosis these endocrine cells may start to play active regulatory roles.This work has been carried out within the projects ‘‘Endocrine Control as a Determinant of Larval Quality in Fish Aquaculture’’ (CT-96-1422) and ‘‘Arrested development: The Molecular and Endocrine Basis of Flatfish Metamorphosis’’ (Q5RS-2002-01192), with financial support from the Commission of the European Communities. However, it does not necessarily reflect the Commission’s views and in no way anticipates its future policy in this area. This project was further supported by the Swedish Council for Agricultural and Forestry Research and Pluriannual funding to CCMAR by the Portuguese Science and Technology Council

Feeding behaviour and digestion physiology in larval fish – current knowledge and gaps and bottlenecks in research

Food uptake follows rules defined by feeding behaviour that determines the kind and quantity of food ingested by fish larvae as well as how live prey and food particles are detected, captured and ingested. Feeding success depends on the progressive development of anatomical characteristics and physiological functions and on the availability of suitable food items throughout larval development. The fish larval stages present eco-morpho-physiological features very different from adults and differ from one species to another. The organoleptic properties, dimensions, detectability, movements characteristics and buoyancy of food items are all crucial features that should be considered, but is often ignored, in feeding regimes. Ontogenetic changes in digestive function lead to limitations in the ability to process certain feedstuffs. There is still a lack of knowledge about the digestion and absorption of various nutrients and about the ontogeny of basic physiological mechanisms in fish larvae, including how they are affected by genetic, dietary and environmental factors. The neural and hormonal regulation of the digestive process and of appetite is critical for optimizing digestion. These processes are still poorly described in fish larvae and attempts to develop optimal feeding regimes are often still on a ‘trial and error’ basis. A holistic understanding of feeding ecology and digestive functions is important for designing diets for fish larvae and the adaptation of rearing conditions to meet requirements for the best presentation of prey and microdiets, and their optimal ingestion, digestion and absorption. More research that targets gaps in our knowledge should advance larval rearing

Linking organisational culture and values with a firm's performance: a case study from the NZ airline industry

The purpose of this research has been two fold. Firstly to conduct a cultural assessment of a New Zealand airline (referred to as “Pukeko Air Ltd.” for confidentiality reasons) in order to identify the perceived current and future preferred organisational culture and organisational values present in this organisation. Secondly to assess how selected organisational members associated the present and future cultural and values profile with organisational performance. A hybrid research methodology was employed, where data was collected in two stages; one quantitative and the other qualitative. First, a quantitative survey questionnaire was distributed to all employees, effectively combining Cameron and Quinn’s (1999) Organisational Culture Assessment Instrument, and McDonald and Gandz’ (1992, p. 69) “Shared values for the modern business corporation”. Second, the results and outcome of the survey formed the basis for six qualitative interviews with senior management staff. The interview questions sought management’s interpretation of survey findings, and in particular the relationship between the current and future cultures and values and associations with organisational performance. The findings from the research show a relatively close alignment between the current and preferred future organisational culture. This signifies that the organisation is in a good situation for the future. Moreover, the research project sought senior staff members’ perceptions of organisational culture’s role in performance. The findings suggest performance is somewhat affected by culture and values, and that these elements helps determining what sort of airline the organisation wants to become, as well as reducing impact of external factors affecting the company. The study indicates not only what type of culture and which values are deemed conducive to success from a management point of view, but also highlights the perceived importance of commitment and ownership in creating a strong culture in this New Zealand Airline